Surface defects and instanton-vortex interaction

par Prof. Nikita SOPENKO (ITEP & IHES)

mardi 18 avr. 2017, 14:30 → 16:00 Europe/Paris

Amphithéâtre Léon Motchane (IHES)

I’ll present a general prescription for the 4d-2d partition function of half-BPS surface defects in d = 4, N = 2 gauge theories in Omega-background which is applicable for any surface defect obtained by gauging a 2d flavour symmetry using a 4d gauge group and reproduces known results obtained via the Higgsing procedure and Kanno-Tachikawa orbifold calculation for Gukov-Witten defects. The role of “negative vortices” which appear in the background of instantons will be emphasized.